4  ■ 


■ 


J 


• 


BUILDER'S  JEWEL; 

OR,  THE 

YOUTH's  INSTRUCTOR, 

AND 

WORKMAN'S  REMEMBRANCER. 

EXPLAINING 

SHORT  and  EASY  RULES, 

Made  familiar  to  the  meaneft  Capacity, 

For  DRAWING  and  WORKING. 

I.  The  Five  Orders  of  Columns  entire;  or  any  Part  of  an 
Order,  without  Regard  to  the  Module  or  Diameter. 

AND    TO   ENRICH  THEM 

With  their  Rufticks,  Flutings,  Cablings,  Dentules,  Modllions,c5V. 

ALSO  TO  PROPORTION 

Their  Doirs%  Windows,  Ititercolumniations,  Porticoes,  and  Arcades. 

TOGETHER  WITH 

Fourteen  Varieties  of  Raking,  Circular,  ^rolled,  Compound,  and  Contracted 
Pediments  ;  and  the  true  Formation  and  Accadering  of  their  Raking  and  re- 
turned Cornices  ;  and  Mouldings  for  Capping  their  Dentules  and  Modi  lions. 

II.  Block  and  Cantaliver  Cornices,  Ruftick  Quoins,  Cornices  pro- 
portioned to  Rooms,  Angle  Brackets,  Mouldings  for  Tabernacle  Frames, 
Panntlling,  and  Centering  for  Groins,  TrulTed  Partit:  i  ,  C".iruers,  Roof*, 
and  Domes.    With  a  Section  of  the  Dome  of  St.  Paul's,  London. 

The  Whole  Illuilrated  by  upwards  of  200  Examples,  engraved  on  103 
Copper  Plates. 

tty  15.  and  T.  LANGLEY. 


THE   FIRST  AMERICAN  EDITION. 


Charlestojfn  :  printed  by  S.  ETHERIDGE, 
For  SAMUEL  HILL,  Evgraver,  N°-  2,  Corhhill, 
BOSTON. 


INTRODUCTION. 


Notwithstanding  there  are  many  volumes 
already  extant,  on  the  lubjeci  of  Architect- 
ure ;  yet,  as  not  one  of  them  is  made  a  fit  iize 
for  the  pocket  ;  and  it  being  an  impoflibility 
for  the  general  part  of  workmen  to  retain  and 
carry  in  their  minds  all  the  ufeful  rules  and  pro- 
portions by  which  works  in  general  are  perform- 
ed, I  have  therefore,  at  the  requeft  of  many 
good  workmen,  and  for  the  fake  of  young  ftu- 
dents,  compiled  this  work  ;  wherein  I  have  re- 
duced the  whole  to  iuch  Ihort  and  eafy  rules, 
that  the  workman  may  not  only  at  the  firll  view 
renew  his  memory  as  occafionspiay  require,  but 
apprentices,  who  may  be  abfolutely  unacquainted 
with  this  noble  art,  and  are  fo  unfortunate,  as 
many  have  been  and  are,  to  be  bound  to  jobbing 
mafters,  who  know  but  little,  may,  without  the 
help  of  any,  by  afliduous  application  at  their 
leifure  hours,  in  evenings  when  the  bufinefs  of 
days  is  over,  &c.  make  themfelves  fuch  mailers 
herein,  that  few  mafters  are  able  or  willing  to 
make  them.  And  indeed  I  muft  own,  that  'tis  a 
a  2  pleafure 


iv 


INTRODUCTION. 


pleafure  to  me,  to  fee  the  fpirit  of  emulation  fo 
powerful  among  young  builders  at  this  time  \ 
when  every  one  of  fenfe  is  endeavouring  to  be- 
come the  moft  excellent  in  his  way,  and  thereby 
make  himfelf  the  moft  ufeful  both  to  himfelf  and 
his  country. 

It  is  ufeful  knowledge  only,  that  makes  one 
man  more  valuable  than  another,  and  efpecially 
that  part  of  knowledge  which  immediately  con- 
cerns the  bufinefs  he  is  to  live  by  ;  and  therefore, 
if  this  work  Ihould  prove  a  help  to  the  improve- 
ment of  knowledge  in  youth  (for  whofe  fakes  'tis 
chiefly  intended),  and  be  no  affront  to  the  fags 
workman,  by  reinforming  him  of  thofe  rules 
which  have  flipt  his  memory,  and  informing  him 
of  others  which  he  never  knew,  it  will  anfwer 
the  denred  end  of  their  hearty  well  wiflier, 


THO.  LANGLEY. 


THE  BUILDER'S  JEWEL. 


5 


CHAP.  I. 


OP  THE  ORDERS  IN  GENERAL,  AND  OF  THEIR  PRINCIPAL  PARTS. 


'HE  Orders  in  general,  are  the  Tufcan,  Dorick,  Ionick,  Co- 


rinthian,  and  Compojite. 
Their  principal  Parts  are  their  Pedeftals,  Columns,  and 
Entablatures. 

The  Height  of  the  Pedeftal  in  every  Order,  is  always  one 
fifth  of  the  whole  Height  of  the  entire  Order. 

The  Height  of  the  Tufcan  Column  is  7  Diameters,  the  Do- 
rick  8,  the  Ionick  9,  and  the  Corinthian  and  Compoftte,  each  10 
Diameters. 

The  Tufcan  Column  is  diminifhed  at  its  Aftragal  or  Neck 
of  its  Capital,  one  4th  of  its  Diameter  next  above  its  Bafc  ; 
the  Dorick  one  5th  ;  the  Ionick,  Corinthian  and  Compojite,  each 
one  6th. 

The  Diminution  of  every  Column  begins  at  one  third  of  the 
Shaft's  Height  above  the  Bafe. 

The  Heights  of  the  Tufcan  and  Dorick  Entablatures  are 
each  equal  to  one  fourth  of  their  Column's  Height  ;  and 
the  Ionick,  Corinthian,  and  Compoftte,  to  one  fifth  of  their 
Column's  Height. 

Thefe  general  Proportions  of  the  principal  Parts  being  firft 
underftood  ;  the  Proportions  of  their  particular  Parts  may 
be  eaftly  underftood  alfo  as  following. 


-Livery  perfect  Pedeftal  confifts  of  three  principal  Parts  : 
Namely,  a  Bafe,  Dado  or  Die,  and  Cornice,  which  are  di- 
vided as  follows. 


CHAP.  II. 


OF    PEDESTALS,   AND   THEIR  PART?. 


The 


6 


THE  BUILDER^  JEWEL. 


The  Dlvifion  of  the  principal  Parts  of  Pedeftals  explained. 

RULE.  Divide  the  given  Height  in  4  Parts,  as  in  Plates 
I.  X.  XXI.  XXXIX.  and  LVII.  Give  the  lower  1  to  the 
Height  of  the  Plinth  ;  one  third  of  the  next  1  to  the  Height 
of  the  Mouldings  on  the  Plinth  ;  half  the  upper  1  to  the 
Height  of  the  Cornice  ;  and  the  Remains  between  will  be  the 
Height  of  the  Dado. 

When  a  Column  is  placed  on  a  Pedeftal,  the  Projection 
of  the  Pedeftal's  Dado,  is  found  by  the  Projection  of  the 
Plinth  to  the  Bafe  of  the  Column  ;  which  always  (lands 
perpendicular  over  the  Upright  of  the  Dado.  But  if  a  Pe- 
deftal is  to  be  made  without  a  Column,  the  Breadth  of  the 
Dado  muft  be  found,  before  we  can  proceed  to  determine 
the  Projections  of  the  feveral  Members  in  the  Bafe  and  in 
the  Cornice  ;  becaufe  'tis  from  the  Upright  of  the  Dado  that 
their  Projections  are  made  ;  and  which  are  found  by  the 
following  Rules. 

The  Breadths  of  Dados  to  Pedeftals  explained. 

RULE  I.  To  find  the  Breadth  of  the  Dado  of  the  Tufcan 
Pedeftal.  Plate  I. 

Divide  the  Height  of  the  Plinth  and  its  Mouldings  in  5 
Parts,  and  the  upper  1  in  7  ;  on  %  with  a  Radius  of  4  cf  die 
great  Parts,  and  4  fevenths,  defcribe  the  Arch  x  g  ;  then  z  g 
is  the  Semi-breadth  required. 

RULE  II.    To  find  the  Breadth  of  the  Dado  of  the  Dorick 

Pedeftal.  Plate  X. 

Divide 


THE  BUILDER'S  JEWEL. 


7 


Divide  the  Height  of  the  Plinth  in  5  Parts,  and  the  upper 
I  in  3,  turn  up  1  of  the  3  Parts  to  and  on  x,  with  the 
Radius  of  5  Parts,  and  laid  one  third,  defcribe  the  Arch  h  y  ; 
then  x  y  is  the  Semi-breadth  required. 

RULE  III.  To  find  the  Breadth  of  the  Dado  of  the  Ionick 
Pedeflal.  Plate  XXI. 

Divide  the  Height  of  die  Plinth  in  three  Parts,  the  upper 
1  in  3  ;  and  the  upper  1  thereof,  in  3  again  ;  then  abating 
the  2  upper  fmall  Parts,  with  the  Remains  of  the  Plinth's 
Height,  on  *,  defcribe  the  Arch  v  y  ;  then  x  y  is  the  Semi- 
breadth  required. 

RULE  IV.  To  find  the  Breadth  of  the  Dado  of  the  Co- 
rinthian and  Compofite  Pedeflals.    Plate  XXXIX.  and  LVII. 

Divide  the  Height  of  the  Plinth  in  3  Parts,  and  the  upper 
1  in  3,  on  .v,  with  the  Radius  of  two  Parts,  and  the  2  thirds, 
defcribe  the  Arch  vy  ;  then  x  y  is  the  Semi-breadth  required. 

Before  I  fhew  how  to  determine  the  Projections  of  the 
Mouldings  on  the  Plinths,  and  in  the  Cornices  of  the  Pedef- 
tals  ;  I  mult  fliew  how  to  divide  their  refpective  Heights. 
And,  firft,  of  the  Mouldings  on  the  Plinths  of  the  feveral 
Pedeltals. 

The  Divijions  of  Mouldings  on  the  Plinths  of  Pedeflals  explained. 

RULE  I.  To  divide  the  Heights  of  the  Mouldings  on  the 
Plinth  of  the  Tufcan  Pedefial.    Plate  I. 

Divide  the  Height  in  6,  as  at  13,  give  the  under  and  upper 
©nes  to  the  Fillets,  and  the  middle  of  4,  to  the  Gm+tcQa» 

RULE 


8 


THE  BUILDER^  JEWEL. 


RULE  II.    To  divide  the  Heights  of  the  Mouldings  &n  the 
Plinth  of  the  Dorick  Pedejlal.    Plate  X. 

Divide  the  Height  in  4  Parts,  as  at  B  ;  give  the  upper  one 
to  the  Cavetto  ;  half  the  next  to  its  Fillet ;  half  the  lower  one 
to  the  lower  Fillet ;  and  the  Remains  to  the  Cima-recla. 

RULE  III.    To  divide  the  Heights  of  the  Mouldings  on  the 
Plinth  of  the  Ionick  Pedejlal.    Plate  XXI. 

Divide  the  Height  in  2,  as  at  B  ;  and  each  in  4  ;  give  the 
upper  1  and  half  to  the  Cavetto  ;  the  next  half  to  its  Fillet ; 
the  next  1  to  the  Aftragal :  the  lower  1  to  the  Fillet ;  and  the 
Remains  to  the  Cima. 

RULE  IV.    To  divide  the  Heights  of  the  Mouldings  on  the 
Plinth  of  the  Corinthian  Pedejlal.    Plate  XXXIX. 

Divide  the  Height  in  4,  as  at  B ;  the  upper  1  and  3d 
downwards,  each  in  3  ;  give  the  upper  1  and  half  to  the 
Cavetto  ;  the  next  half  to  the  Fillet ;  the  next  1  to  the  Aftra- 
gal ;  the  lower  4th  to  the  Height  of  the  Torus  ;  and  one 
third  of  the  next  to  its  Fillet. 

RULE  V.  To  divide  the  Heights  of  the  Mouldings  on  the 
Plinth  of  the  Cornpofite  Pedejlal.    Plate  LVII. 

Divide  the  Height  in  4  ;  and  the  upper  and  third  Part, 
downwards,  each  in  3  ;  give  the  upper  2  of  the  upper  Part, 
to  the  Cavetto  ;  the  next  to  its  Fillet  ;  the  lower  4th  Part  to 
the  Torus,  and  one  third  of  the  next  Part  to  its  Fillet. 

The  Dhijton  of  Mouldings  in  the  Cornices  of  Pedejlals  explained. 

RULE  I.  To  divide  the  Heights  of  the  Mouldings  contained 
in  the  Cornice  of  the  Tufcan  PedefaL   Plate  I. 

Divide 


THE  BUILDER^  JEWEL. 


9 


Divide  the  Height,  as  at  A,  in  6  Parts  ;  give  the  upper  1 
to  the  Regula ;  the  next  3  to  the  Plat-band,  and  the  lower  z 
to  the  Cima-reverfa* 

RULE  II.  To  divide  the  Heights  of  the  Mouldings  contained 
in  the  Cornice  of  the  Doric  k  PedeJiaL    Plate  X. 

Divide  the  Height,  as  at  A,  in  4  ;  give  half  the  upper  1  to 
the  Regula  ;  the  next  1  and  half  to  the  Plat-band  ;  the  next 
1  to  the  Ovolo  ;  the  upper  one  third  of  the  lower  1  to  the 
Fillet ;  and  the  remaining  two  third*  of  the  lower  1  to  the 
Cavetto. 

RULE  III.    To  divide  the  Heights  ofthelftouldingscontain- 

td  in  the  Cornice  of  the  Ionick  Pedejlal.    Plate  XXL 

Divide  the  Height  in  1 2  Parts,  as  at  A  ;  give  the  upper 
one  to  the  Regula  ;  the  next  2  to  its  Cima-reverfa ;  the  next  3 
to  the  Plat-band  ;  the  next  3  to  the  Ovolo  ;  the  next  1  to  the 
Aftragal :  Half  the  next  1  to  its  Fillet,  and  the  Remains  1  and 
a  half  to  the  Cavetto. 

RULE  IV.  To  divide  the  Heights  of  the  Mouldings  contained 
in  the  Cornice  of  the  Corinthian  PedeJiaL    Plate  XXXIX. 

Divide  die  Height  in  3,  as  at  A  ;  alfo  the  upper  1  in  6,  the 
lower  half  of  the  middle  1  in  3,  and  the  lower  half  of  the 
lower  1  in  3.  Of  the  6  upper  fmall  Parts,  give  the  upper  1 
and  one  third  to  the  Regula  ;  the  remaining  two  thirds  and 
two  Parts  to  the  Cima-reverfa  ;  and  the  next  1  to  the  Aftra- 
gal. Give  the  laft  1,  and  half  the  middle  great  Part,  to  the 
Plat-band :  Alfo  one  third  of  the  remaining  half  to  the 
Fillet  on  the  Cima-recla  ;  and  the  remaining  two  thirds, 
and  upper  half  of  the  lower  great  Part  to  the  Cima-retla. 

B  ^  LalUy, 


IQ  THE  BUILDER^  JEWEL. 

Laftly,  give  the  upper  i  Part  of  the  half  of  the  lower  Part  to 
the  Aftragal ;  half  the  next  to  its  Fillet,  and  the  Remains  to 
the  Cavetto. 

RULE  V.  To  divide  the  Heights  of  the  Mouldings  contained 
m  the  Cornice  of  the  Compofite  PedeflaL    Plate  LVII. 

Divide  the  Height  in  6  Parts,  as  at  A;  give  half  the  up- 
per i  to  the  Regula  ;  the  next  I  to  the  Cima-reverfa ;  the 
next  i  and  half  to  the  Plat-band  ;  one  third  of  the  next  i  to 
the  Fillet  on  the  Cima-refta  ;  the  remaining  two  thirds,  and 
the  next  i ,  to  the  Cima-recla  ;  one  third  of  the  laft  i  to  the 
Fillet  on  the  Cavetto  ;  and  the  remaining  two  thirds  to  the 
Cavetto. 

The  Heights  of  the  feveral  Mouldings  on  the  Plinths,  and 
in  the  Cornices,  being  thus  found  ;  I  fhall  proceed  to  mew 
how  to  give  each  its  proper  Projecture  from  the  Upright  of 
their  Dados. 

The  Projections  of  the  Plinths,  and  Members  on  the  Plinths^  and 
in  the  Cornices  of  Pedeflals  explained. 

Make  the  Projection  of  the  Plinth  from  the  Upright  of  its 
Dado,  in  every  Order,  equal  to  the  Height  of  the  Mouldings 
on  the  Plinth  ;  and  make  the  Projection  of  every  Cornice  the 
fame. 

To  fi?id  the  Projections  of  the  feveral  Members. 

Divide  the  Projection  of  the  Tufcan  Plinth  in  6,  and  of 
all  the  other  Orders  in  4  ;  and  then  fubdividing  the  Parts,  as 
exhibited  in  the  Scales  of  Projection,  which  are  placed  be- 
tween the  Bafe  and  Cornice  of  each  Pedeftal :  from  thence, 

flop  ; 


THE   BUILDER^  JEWEL. 


ftop  ;  or  terminate  the  Projection  of  each  Member,  as  by  In- 
fpection  is  {hewn  ;  and  thus  are  the  five  Orders  of  Pedeftals 
completed. 

CHAP.  III. 

Of  Columns  and  their  Parts* 

A  column  confitts  of  three  principal  Parts,  viz*  A  Bafe, 
Shaft,  and  Capital. 

The  Height  of  Columns  explained. 
To  find  the  Heights  of  Columns  *  having  the  Heights    of  the 
Columns  and  Entablatures  given,  thefe  are  the  Rules. 

RULE  L  In  the  Tufcan  and  Dorick  Orders.  Plate  L 
and  X. 

Divide  the  given  Height  of  the  Column  and  Entablature 
in  5  Parts  ;  the  upper  i  is  the  Height  of  the  Entablature, 
and  the  lower  4  of  the  Column.  Divide  the  Height  of  the 
Tufcan  Column  in  7,  and  of  the  Dorick  in  8  ;  and  ene  is  the 
Diameter  of  the  Column. 

RULE  II.  In  the  Ionick,  Corinthian,  and  Compofite  Or* 
ders.    Plates  XXI.  XXXIX.  and  LVII. 

Divide  the  given  Height  of  the  Column  and  Entablature, 
in  6  Parts  :  the  upper  1  is  the  Height  of  the  Entablature, 
and  the  lower  5  of  the  Column.  Divide  the  Height  of  the 
Ionick  Column  in  9,  and  the  Corinthian  and  Compofite  Columns 
each  in  10  Parts,  and  1  is  the  Diameter. 

The  Heights  and  Projeclions  of  the  Bafts  of  Columns  explained. 

The  Height  of  the  Bafe  of  every  Column,  is  precifely  half 
its  Diameter  next  above  the  Bafe  j  and  the  Projection  of  the 
B  2  Plinth, 


12 


THE  BUILDERS  JEWEL. 


Plinth,  from  the  Upright  of  the  Shaft,  is  always  equal  td 
one  6th  of  the  Column's  Diameter. 

The  Height  of  Plinths  to  the  Bafes  of  Columns',  is  either 
equal  to  half  the  Height  of  the  whole  Bafe,  as  in  the  Tufcan 
Bafe,  Plate  II.  or  to  one  third  of  the  Bafe's  Height,  as  in  the 
Dorick  Bafe  on  the  Right-hand  Side,  Plate  XL  And  in  the 
fenick,  Corinthian  and  Composite  Bafes,  Plates  XXII.  XLL 
and  LVIII. 

To  make  the  Conjlruclion  of  Bafes  to  Columns  eajy,  I  will  ex- 
plain, How  to  divide  the  Heights,  and  terminate  the  Projec- 
tions of  the  Members  contained  in  the  Tufcan  and  Dorick 
Bafes;  by  which  thofe  of  the  Ionick9  Corinthian  and  £ompo- 
ftte  will  be  underftood,  as  being  no  more  than  Repetitions  of 
the  like  Rules. 

RULE  I.  To  divide  the  H eights  >  and  terminate  the  Projec- 
tions of  the  Members  contained  in  the  Bafe  of  the  Tufcan  Column. 
Plate  ft 

L    To  determine  their  Heights* 

Divide  the  Height  in  two,  and  give  the  lower  I  to  the 
Plinth,  as  aforefaid.  Divide  the  upper  i  in  4  ;  give  the  lower 
3  to  the  Torus,  and  the  upper  1  to  the  Cincture. 

II.    To  determine  their  Projeclurcs. 

Divide  the  Projection  of  the  Plinth,  from  the  Upright  of 
the  Shaft  in  4  Parts,  and  the  fecond  Part  in  4  ;  then  1  Part 
and  3  fourths  of  the  fecond,  flops  the  Cincture  ;  and  the 
Torus  is  always  in  every  Order  die  fame  Projection  as  the 
Plinth. 

RULE 


THE  BriLDER*S  JEWEL. 


RULE  II.  To  divide  the  Heights,  and  terminate  the  Pro- 
jeclions  of  the  Members  contained  in  the  Attick  Safe  to  the 
Dorick  Column,  on  the  Right-hand  Side  of  Plate  XI. 

I.     To  determine  their  Heights. 

Divide  the  Height  in  3  Parts,  the  middle  Part  in  4,  and 
the  upper  Part  in  2  :  Give  the  lower  1  Part  to  the  Plinth,  as 
aforefaid  ;  three  fourths  of  the  next  to  the  lower  Torus  ; 
and  half  die  upper  1  to  the  upper  Torus.  Divide  the  Re- 
mainder between  the  two  Torufes  in  6  ;  give  the  upper  and 
lower  ones  to  the  two  Fillets  ;  and  the  middle  4  to  the 
Scotia* 

~"      IL    71?  determine  their  Projttivm. 

Divide  the  Projection  of  the  Plinth  in  4  Parts,  and  the  2d 
and  3d  Parts  in  halves  ;  from  whence  perpendicular  Lines  be- 
ing drawn  up,  will  terminate  the  Cincture,  and  the  two  Fil- 
lets of  the  Scotia* 

RULE  I.    To  defcribe  the  Curve  of  this  Scotia. 

Divide  the  Height  in  3  Parts,  as  at  B  ;  and  draw  the  Lines 
c  h  2  and  a  b.  On  by  defcribe  the  Quadrant  a  c  ;  and  on  the 
Point  2,  the  Arch  c  d>  which  together  form  the  Curve  of 
the  Scotia  to  the  Attick  Bale. 

/  will  elf  now  fyenvy  how  to  defcribe  the  Scotia  in  the  Ionick, 
Corinthian  and  Compofite  Baft;,  as  esprejfed  at  large  by 
Figure  A.    Plate  XLI. 

Divide  the  Height  b  g  in  7  Parts,  from  the  third  Part  dravr 
f  c  parallel  to  the  Fillets,  and  equal  to  3  Parts  ;  thro*  the 
Point  /  draw  the  Line  a  e  parallel  to  b  g,  and  make  f  a  equal 

to 


*4 


THE  BUILDER'S  JEWEL. 


to  4  Parts  of  b  g  :  Diaw  a  c,  and  then,  on  the  Point  r,  de- 
fcribe  the  Arch  b  x  d>  and  on  a  the  Arch  d  e. 

Having  thus  explained  the  Bafes,  or  firft  Parts  of  Columns, 
I  fliall  now  proceed  to  the  fecond  Parts,  which  is  their  Shafts. 

The  Shaft  of  a  Column  is  that  Part,  which  is  contained 
between  its  Bafe  and  Capital ;  and  confifts  of  3  Parts,  viz. 
its  Cincture,  Trunk,  and  Aftragal ;  excepting  in  the  Tufcany 
where  the  Cincture  is  made  a  Part  of  the  Bafe  to  the  Column. 

To,  render  the  Shafts  of  Columns  agreeable  to  the  taper 
Growth  of  the  Trunks  of  Trees,  (with  which  the  firft  Col- 
umns were  made)  their  Shafts,  or  rather  their  Trunks  are 
therefore  diminifhed  from  the  lower  third  Part,  up  uato  the 
Aftragal,  as  following. 

The  Shafts  of  Columns,  and  their  Diminution  explained. 

RULE.  To  diminijh  the  Shaft  of  a  Column.   Plate  I.  Fig.  A. 

Set  up  the  Shaft's  Height ;  at  i  k>  its  Aftragal,  fet  off  its 
diminifhed  Diameter,  viz.  three  fourths,  as  being  Tufcan. 
Complete  the  lower  third  undiminished  Part  of  the  Shaft, 
and  on  a  d  its  upper  Part  defcribe  the  Semicircle  abed. 
From  /  ky  draw  the  Lines  i  b,  k  c,  parallel  to  /;  n  the  central 
Line,  cutting  the  Semicircle  in  b  and  c.  Divide  the  Arches 
a  b  and  c  d9  each  into  any  fame  Number  of  Parts,  fuppofe  4  : 
and  divide  h  n  into  the  fame  Number  of  Parts  alfo,  as  at  the 
Points  gfe ;  through  which  draw  right  Lines  at  right  An- 
gles to  h  n  of  Length  at  Pleafure,  From  the  4  Divifions  in 
the  Arch  ab,  to  thofe  in  the  Arch  c  d,  draw  Ordnates  (as 
thofe  dotted).    Make  the  Diameter  of  the  Shaft  at  e  equal 

to 


THE  BUILDER'S  JEWEL.  1 5 

to  the  Length  of  the  firft  Ordnate  :  at  f,  to  the  Length  of 
the  fecond  Ordnate  ;  and  at  g,  to  the  Length  of  the  third 
Ordnate.  Then  from  the  Points  /  k,  through  the  Extremes 
of  the  Diameters  gfe,  to  the  Points  ad,  trace  the  Contours 
or  Out-lines  of  the  Shaft's  Diminution. 

*  The  Manner  of  Ruftic -citing  the  Shafts  of  Cohurnis  explained. 
The  Shafts  of  the  Tufcan,  Dorick,  and  Ionick  Columns,  are 
Sometimes  Rufticated  ;  but  thofe  of  tlie  Corinthian  and  Coin- 
pofite  feldom  or  never. 

RULE.    To  Rujlicate  the  Tufcan,  Dorick,  and  Ionick  Shafts. 

Divide  the  Height  of  the  Tufcan  in  7,  as  in  Plate  L  the 
Dorick  in  8,  as  in  Plate  X.  and  the  Ionick  in  9,  as  'in  Plate 
XXI,  then  the  Blocks  and  Intervals  in  the  Tufcan  and  Ionick 
will  each  be  1  Diameter,  and  thofe  of  the  Dorick,  two  Di- 
ameters. 

The  Projection  of  the  Blocks  is  'generally  made  equal  to 
the  Projection  of  the  Plinth,  as  cxprcffcd  ii)$he  Tvfcan  Ol  der, 
Plate  I.  and  continued  upright  without  Diminution  ;  but  as 
the  upper  Parts  of  the  Shafts  feem  thereby  overcharged,  I 
therefore  recommend  the  Diminution  to  be  parallel  with  the 
Shaft,  as  in  the  Dorick  Order,  Plate  X. 

The  Mariner  of  Fluting  the  Shafts  of  Columns  explained. 

The  Shafts  of  the  Dorick,  Ionick,  Corinthian,  and  Comp'Jite 
Columns,  are  fometimes  fluted  and  cabled  ;  but  the  Shaft  of 
the  Tufcan  Column  feldom  or  never  was,  <as  being  r:n  Embel- 
lishment too  gaudy  for  fo  robuft  and  fimple  an  Order,  whofe 
Beauty  ccnfifts  in  its  native  Plainnefs  ;  mid  indeed  all  Columns 
C  l:v.;? 


i6 


THE  BUILDER'S  JEWEL* 


have  a  grander  Afpecl:  when  entirely  plain,  than  when  Rus- 
ticated or  Fluted.  The  Dorick  Shaft,  with  refpect.  to  its 
Herculean  Afpecl,  ihould  not  be  fluted  ;  but  as  the  Ancients 
difpenfed  therewith,  the  Moderns  frequently  do  the  fame 
But  however,  as  herein  Majefty  muft  be  preserved,  therefore 
the  Ancients  allowed  but  20  Flutes,  and  thofe  without  Fil- 
lets, as  in  the  Left-fide  of  Plate  XI.  thereby  making  them 
of  a  mafculine  Afpecl ;  whilft  thofe  of  the  lonick  and  Corin- 
thian Shafts  are  charged  with  24  Flutes,  and  as  many  Fil- 
lets (each  of  which  is  equal  to  one  third  of  a  Flute)  which 
renders  them  lefs  capacious  and  of  an  effeminate  Afpecl, 
agreeable  to  the  Characters  of  thofe  Orders. 

RULE.    To  divide  the  Flutes  of  a  Dorick  Column.  Plate  XL 

Divide  the  Circumference  into  20  equal  Parts,  and  draw 
Lines,  thereby  making  a  Polygon  of  20  Sides  ;  on  each  Side 
complete  an  equilateral  fpherical  Triangle,  as  a  b  c  on  the 
Left  of  Plate  XI.  and  on  the  external  Angle,  as  b,  defcribe 
the  Curve  a  r,  which  is  the  Depth  or  Sinking-in  of  a  Flute. 

RULE.  35?  divide  the  Flutes  and  Fillets  of  an  lonick,  Co- 
rinthian or  Cornpofite  Column.    Plate  XXV. 

Divide  the  Circumference  of  the  Semi-Column  in  1 2  Parts, 
and  each  Part  in  8,  as  a  b.  Give  3  Parts  to  each  Semi-Flute 
as  #J)9  and  i  b  ;  and  2  Parts  to  each  Fillet,  as  h  h 

The  Sinkings  or  Depths  of  thefe  Fillets  are  either  the  Arch 
•f  a  Quadrant,  as  thofe  on  the  Right  hand  defcribe d  on  the 
Centers  c  s,  &c.  or  cf  a  Semi-Circle;  as  thofe  on  the  Left  de- 
k:'ib:  J  pa  ;Le  Centers  x  x9  &c, 

RULE 


THE   BUILDER^  JEWEL. 


J7 


RULE.  To  defcribe  Cablings,  in  the  Flutes  of  a  Column. 
Plate  XXV. 

On  the  Points  z  %%  with  the  Radius  z  x,  defcribe  the  Arches 
y-xoy  jxo,  &c.  which  are  the  Bafes  of  the  Cablings,  and 
whofe  Height  finifiies  at  the  firft  third  Part  of  the  Shaft's 
Height. 

RULE.  To  fet  out  Flutes  and  Fillets  on  the  Skafl  of  a  Column. 
Plate  XXVI. 

On  a  Pannel,  &c.  draw  a  right  Line,  as  a  b,  and  thereon 
fet  off  24  equal  Parts  at  Pleaiure,  which  together  mud  al- 
ways be  lefs  than  the  Girt  at  the  Aftragal  of  the  Column  to 
be  fluted. 

Divide  any  1  Part  in  4  Parts,  and  take  one  Part  in  the 
Compaffes,  and  fet  it  off  in  every  of  the  other  2  3  Parts  ;  and 
from  the  feveral  Parts  fo  divided  (which  will  be  to  one  an- 
other as  1  is  to  3  ;  that  is,  a  Fillet  to  a  Flute)  draw  up  right 
Lines  at  right  Angles  from  the  divided  Line.  This  done, 
ftrike  a  perpendicular  Chalk-Line  down  the  Front  of  the 
Column.  And  being  provided  with  two  ftraight-edged  Pieces 
of  Parchment,  &c.  therewith  girt  the  Column  at  its  Bafe, 
and  at  its  Aftragal.  Apply  the  Girts  fo  taken  to  the  paral- 
lel Lines  aforefaid,  fo  that  their  Extremes  fhall  juft  touch  the 
two  outer  Parallels,  as  at  e  c  and  d  f  Then  keeping  them 
there,  with  a  Pencil  mark  their  Edges  at  the  Meeting  of 
each  Parallel ;  and  thereby  the  two  Girts  will  be  divided  in 
to  the  Flutes  and  Fillets,  agreeable  to  your  Column  to  be 
fluted.  This  done,  apply  any  End  of  each  of  the  Parch- 
ment Girts  to  the  Bottom  and  the  Top  cf  the  Front  Cen- 
tral-Line :  and  then  embracing  the  Column  at  its  Bafe  and 
C  2  Aftragal, 


rS 


THE  EUILDER*S  JEWEL. 


A-ftragal,  remove  each  Girt  until  you  bring  tlie  Middle  of 
a  Flute  on  the  central  Line  ;  and  then  prick  off  the  Breadth 
of  every  Flute  and  Fillet  in  the  two  Girts,  which  will  ftand 
exactly  perpendicular  over  each  other. 

Note,  In  large  Columns  it  may  be  neceffary  to  fet  out  the 
Breadths  of  the  Flutes  and  Fillets,  in  one  or  more  Places, 
between  the  firft  third  Part  of  the  Shaft's  Height  and  the 
Aftragal  ;  which,  when  required,  may  be  moft  exactly  done, 
by  girting  at  the  Parts  required  ;  and  proceeding  afterwards 
in  every  other  refpect  as  afore  faid, 

'The  Fluting  of  Pilajlers  explained. 

RULE.  To  flute  a  Pilajler  with  Fillets,  and  a  Bead  at  each 
%uom,    Plate  XXXVIL 

Draw  a 'Line  at  Pleafure,  as  ah,  and  thereon  fet  31  equal 
Parts,  which  together  fhall  be  greater  than  die  Pilafhr  to 
be  fluted.    Take  the  3 1  Parts  in  your  Compares,   &c.  and 
on  the  firft  and  Iaft  Points  make  the  Section  c,  and  draw  the 
Lines  c  a  and  c  b,  which  will  complete  an  equilateral  Triangle. 
Set  the  Breadth  of  the  pilafter  from  c  to  d  and  to  e,  and 
draw  the  Line  d  €,  which  being  parallel  to  a  h,  is  therefore 
equal  to  the  Breadth  of  the  Pilafter.     Now  right  Lines 
drawn  from  the  31  Parts  to  the  Point  c,  they  will  divide 
the  Line  d  e  in  fimilar  31  Parts  alfo.    Of  which  give  the  two 
outer  Parts  to  the  two  Beads  at  the  Quoins  ;  the  next  two 
outer  ones,  to  the  two  outer  Fillets  ;    the  next   3    to  the 
Breadth  of  a  Flute  ;  the  next  1  to  a  Fillet  ;  the  next  3  to  a 
Flute  ;  the  next  1  to  a  Fillet,  &c. 


THE  BUILDER'S  JEWEL. 


19 


Note,  By  the  fame  Rule  a  Pilader  with  Flutes  and  Fillets 
only,  as  Fig.  A,  is  divided  from  29  Parts,  firft  fet  off  at  Plea- 
fure  ;  and  then  proceeding  as  before. 

Having  thus  explained  the  Bafes  and  Shafts  cf  Columns, 
&c.  I  mail  now  proceed  to  their  Capitals. 

Of  Capitals,  there  are  two  Kinds,  viz.  the  one  confiding 
of  Mouldings  only  ;  as  thofe  of  the  Tufcan  and  D  crick  ;  and 
the  other  of  Mouldings  and  fculptured  Ornaments,  as  the 
Ionic  ky  Corinthian,  and  Ccmpofite. 

The  Heights  of  Capitals  explained. 
The  Height  of  the  Tufcan  and  Dorick  Capitals,  are  eacn 
precifely  a  Semi-diameter,  as  in  Plates  II.  and  XI.  The 
Height  cf  the  ancient  Ionick  Capital,  in  its  Mouldings  above 
die  Adragal  of  the  Shaft,  is  but  one  third  of  a  Diameter, 
or  20  Minutes  ;  but  including  the  Depth  of  its  Volute,  it  fa 
35  Minutes,  as  in  Plate  XXIII.  which  exceeds  the  Volute 
to  the  modern  Capital  by  5  Minutes.  The  Height  of  the 
Corinthian  Capital  is  one  Diameter,  and  one  fixth,  as  alfo  is 
the  Height  of  die  Compcfite  Capital. 

The  Divifions  and  Prcj eel  ions  of  the  Members  in  the  Tufcan  and 
Dorick  Capitals  explained.    Plates  II.  and  XI. 

RULE  I.  To  divide  the  Heights  and  determine  the  Pro- 
jections of  the  Members  in  the  Capital  of  a  Tufcan  Column  cr 
Pilader. 

I.    To  divide  the  Heights  of  the  Members.    Plate  II. 
Divide   the   Height   in  3    Parts  (as  on  the  Left-fide.) 
Divide  the  middle  1  in  6  :  of  which  give  the  lower  1  to  the 
Fillet  under  the  Ovclo;    and  the  other  5  to  the  Ovolo. 

Divide 


20 


THE  BUILDER^  JEWEL. 


Divide  the  Tipper  i  into  4 ;  give  the  upper  1  to  the  Fillet ; 
and  the  other  3  to  the  Fafcia  of  the  Abacus.  Set  down 
a  b,  half  the  Height  of  the  Frize  or  Neck  of  the  Capital, 
from  b  to  c,  and  divide  it  in  3  Parts ;  give  the  upper  2  to  the 
Aftragal ;  and  the  lower  one  to  its  Fillet. 

II.     71?  determine  the  Projections. 

Divide  the  Semi-diameter  of  the  Column  at  its  Aftragal 
(as  is  done  above  on  the  Capital)  in  6  Parts,  and  give  3  to 
the  Projeclion  of  the  upper  Fillet. 

But  if  the  Capital  is  of  an  undiminifhed  Pilafter,  (as  on 
the  Right-hand  fide  of  Plate  II.)  then  divide  the  Semi- 
diameter  of  the  Pilafter  (as  above  on  the  Capital)  in  8  Parts, 
and  give  three  to  the  Projection,  as  before. 

Note,  By  the  Scale  of  Projeclion,  placed  againft  the 
Neck  of  the  Capital,  you  fee  that  the  whole  Projeclion  is 
divided  in  3  ;  the  firft  1  in  2  ;  and  the  laft  1  in  4;  the 
half  of  the  firft  1  flops  the  Projeclion  of  the  Fillets  under 
the  Aftragal  and  Ovolo  ;  and  the  2  firft  of  the  4,  in  the  outer 
1  third  Part,  ftops  the  Ovolo  and  Fafcia  of  the  Abacus. 

RULE  II.  To  divide  the  Heights ,  and  determine  the  Projec- 
tions of  the  Members  contained  in  the  Capital  of  a  Dorick  Co* 
lumn  or  Pilafter.    Plate  XI. 

I.     71?  divide  the  Heights  of  the  Members. 
Divide  the  Height  in  3  Parts  (as  on  the  Left-fide)  divide 
the  middle  1  in  3  ;  of  which  the  lower  1  divided  in  3,  give 
the  upper  2  to  the  Aftragal,  and  the  lower  i^io  the  Fillet. 
Divide  the  upper  3d  Part  in  3  ;  give  the  lower  2  to  the  Fafcia 


THE  BUILDER'S  JEWEL. 


of  the  Abacas ;  and  the  upper  i  thereof  divided  in  3,  give 
the  upper  1  to  the  Fillet,  and  the  lower  2  to  the  Crma-reverfa. 

Note,  The  Height  of  the  Aftragal  to  the  Shaft  is  found,  as 
before,  in  the  Tufcan  Column,  Pages  19,  20. 

II.     To  determine  their  Prcjeclion. 

Divide  the  Semi-diameter  of  the  Column  at  its  Aftragal 
(as  above  on  the  Capital)  in  4  ;  and  give  2  to  the  Projection 
of  the  upper  Fillet*  But  if  the  Capital  is  of  an  undiminifhed 
Pila-ter,  (as  on  the  Right-hand  fide)  then  divide  the  Semi- 
diameter  of  the  Pilafter  (as  above  on  the  Capital)  in  5  Parts, 
and  give  2  to  the  Projection,  as  before. 

By  the  Scales  of  Projection  on  each  Side  of  the  Capital, 
you  fee,  that  the  whole  Projection  is  there  divided  in  4  Parts ; 
from  which,  and  their  Sub-divifions,  thefeveral  Members  in 
the  two  Varieties  of  Capitals  have  their  Projections  deter- 
mined. 

The  ancient  Ionick  Capital,  and  its  Volute  explained. 
Plate  XXIII. 

RULE.  I  To  divide  the  Height  of  its  Members,  and 
defcribe  its  Volute. 

L  To  divide  the  Height  of  its  Members* 
Divide  the  given  Height  as  k  x,  in  1 1  Parts ;  give  the  up- 
per one  to  the  upper  Fillet ;  the  next  2  to  the  Cima-reverfa, 
which  with  the  aforefaid  Fillet  makes  the  Abacus :  give  the 
next  1  to  the  Lift  of  the  Volute ;  the  next  3  to  the  Bard  of 
the  Volute  ;  and  the  remaining  4  to  the  Ovolo.  This  done, 
fet  down  8  of  the  above  1 1  Parts  from  x  to  I  ;  give  the 
irft  2  to  the  Aftragal ;  the  next  1  to  its  Fillet ;  and  the 

lower 


22 


THE  BUILDER^  JEWEL. 


lower  5  to  the  Depth  of  the  Volute.  Divide  r  s  on  the 
Right-hand  (which  is  equal  to  k  x9  or  20  Minutes,  the  Height 
of  the  Mouldings  of  the  Capital)  in  4  Parts,  and  turn  down 
1  Part  to  d ;  then  r  d  will  be  equal  to  25  Minutes,  which  is 
equal  to  the  Semi-diameter  of  the  Column  at  its  Shaft. 
Now  admitting  b  v  to  be  the  central-Line  of  the  Column, 
make  v  c  equal  to  r  d,  and  draw  the  Line  e  c  6>  which  will  be 
the  upright  of  the  Column.  Make  h  g  equal  to  two  thirds 
of  a  1,  the  Height  of  the  Aflragal  ;  and  from  the  Points- 
draw  the  Cathetus  or  Line  f  g,  parallel  to  the  central  Line. 
Divide  g  h  in  4  Parts ;  the  firft  1  flops  the  Aftragal  at  a. 
Make  f  n  equal  to  f  /,  which  will  terminate  the  Projection  of 
the  Abacus. 

RULE  II.    To  defcrihe  the  Ionick  Volute.    Plate  XXIIL 

From  1  Part  below  x9  draw  the  Line p  mo  for  the  central 
Line  of  the  Aftragal,  interfering  the  Cathetus  i  g  in  0.  On 
the  Point  <?,  with  the  Radius  0  z,  defcribe  the  Circle  or  Eye 
of  the  Volute  (which  is  reprefented  at  large  by  the  Figure 
R)  :  wherein  infcribe  the  Geometrical  Square,  and  draw  its 
Diameters  2,  4;  and  r,  3;  divide  each  Semi-diameter  in  3 
Parts,  as  at  the  Points  6.  10  ;  5.  9  \  1 2.  6 ;  and  1 1.  7  :  which 
are  the  Centers  numbered  in  Order,  on  which  the  Outline 
of  the  Volute  is  defcribed,  viz.  The  Point  1  is  the  Center  to 
the  Arch  im ;  the  Point  2,  of  the  Arch  nig  ;  the  Point  3,  of 
the  Arch  g  />,  &c. 

The  inward  Line  of  the  Lift  of  the  Volute  is  defcribed  on 
1 2  other  Centers,  which  are  at  one  Fifth  of  the  Diftance 
between  the  other  12  Centers,  and  which  are  fignified  by 

the 


THE   BUILDEr/s  JEWEL. 


the  fftiall  Diviiions  next  within  the  12  Centers  in  the  Eye  of 
the  Volute  at  large,  in  Plate  XII. 

To  gradually  diminifli  the  Lift  of  this  Volute,  we  mull  di- 
vide its  Height  or  Breadth  in  12  Parts,  as  exprefled  above, 
in  PI.  XXII.  and  at  every  Quarter  of  its  Rotation,  abate  ifs 
Breadth  1  of  thofe  Parts,  as  exprelled  by  the  Numerical 
Figures  affixed,  which  will  caUle  it  to  terminate  at  the  Eye 
in  a  Point. 

Note,  Fig.  AB,  PI.  XXIII.  is  a  View  cf  half  a  Side  of  the 
Capital,  wherein  B  (hews  the  Thicknefs  of  the  Volute,  whofe 
Height  is  equal  to  ig  in  the  Front.  The  Heights  of  the  other 
Parts  are  ihewn  by  the  Scale  of  Parts  on  the  Left  ;  and  is 
the  fame  as  the  like  Scale  above. 

Note,  The  Abacus  to  this  Capital  being  fquare,  is  therefore 
called  by  Workmen  a  Trencher  Capital ;  and  indeed  very  prop- 
erly, becaufe  the  Word  Abacus  is  derived  from  the  Greek 
Word  Max,  fignifying  a  Square  Trencher. 

The  Modem  Ionick  Capital  explained.     Plate  XXIV. 

RULE.  To  divide  the  Heights  of  the  Memhers  contained  in 
its  Abacus,  and  to  determine  their  Projections* 

This  Capital,  though  called  Modern,  was  invented  by 
Vincent  Scamozzi;  and  including  its  Volute,  is  preciiely  half 
a  Diameter  in  Height. 

L    To  find  the  Heights  of  the  Members. 
Divide  its  Height  in  3  Parts,  and  the  upper  half  of  the 
upper  1  in  4,  as  on  the  Left ;  of  which  give  the  upper  3  to  the 
D  Ovolo ; 


24 


THE  BUILDER^  JEWEL. 


Ovolo  ;  and  the  other  i  to  the  Fillet  under  It.  Divide  the 
lower  2  Parts  and  half  in  8  Parts  (as  on  the  Right)  give  the 
upper  i  and  half  to  the  Fafcia  of  the  Abacus  ;  the  next  half  to 
the  Recefs  under  the  Abacus  ;  the  next  2  to  the  Ovolo  ;  the 
next  i  to  the  Aftragal ;  and  the  next  half  to  its  Fillet. 

II.    To  find  the  Projeftures  of  the  Members. 

Draw  the  central  Line  of  the  Column  h  g  ;  and  in  any 
Place,  as  at  g,  draw  the  Line  a  b  at  right  Angles  to  h  g,  and 
of  Length  at  Pleafure.  Make  g  e  and  g  d,  each  equal  to  the 
Semi-diameter  i  k  ;  and  divide  it  into  1 2  Parts,  each  reprefent- 
ing  5  Minutes  (or  i-i2th  of  a  Diameter)  ;  make  c  a  and  d  b, 
each  equal  to  15  Minutes  or  1 -fourth  of  a  Diameter,  which 
terminates  the  Projection  of  the  extreme  Parts  or  returned 
Horns  of  the  Abacus  ;  as  exhibited  by  the  dotted  parallel  Lines 
drawn  thence  up  to  them. 

And  from  the  Sub-divifions  of  the  2  outer  5  Minutes,  tht 
Projections  of  the  other  Parts  of  the  Abacus  are  determined 
in  the  fame  manner ;  as  alfo  are  the  Projections  of  the  Ovolo, 
Aftragal,  and  Fillet,  reprefented  by  dotted  Lines  within  the 
Volute. 

The  Volute  of  this  Capital  is  reprefented  in  Plate  XXIL 
nnd  is  defcribed  the  fame  as  that  of  the  ancient  Capital  ;  for 
though  it  appears  to  be  elliptical  when  feen  in  a  direct  View, 
as  being  thereby  fomething  forefhortened ;  yet  it  is  circular, 
as  the  other. 

Under  this  Capital  I  have  placed  half  its  Plan,  whofe  Con- 
traction being  plainly  exhibited  by  the  dotted  perpendicular 

Lines, 


THE  BUILDER'S  JEWEL. 


25 


Lines,  proceeding  from  the  Members  in  the  Elevation,  needs 
no  further  explanation. 

The  Corinthian  Capital  explained.    Plate  XLI. 

This  Capital  was  originally  adorned  with  the  Acanthus 
Leaves  only  ;  hut  as  fome  delight  in  Variety,  I  have  therefore 
in  Plate  XI.  given  the  Acanthus  with  the  Olive,  Laurel,  and 
Parfley,  to  be  employed  at  difcretion. 

The  Height  of  this  Capital  was  originally  but  1  Diameter  : 
but  modern  Architects  thinking  it  too  fhort,  they  therefore 
added  10  Minutes,  thereby  making  its  Height  70  Minutes, 
r*nd  giving  it  a  much  more  magnificent  afpect  than  it  had 
before. 

By  the  Meafures  affixed,  which  are  no  more  than  the  Height 
divided  in  7  Parts,  of  which  the  upper  one  is  the  Abacus  ;  the 
Height  of  every  Part  is  adjufted  ;  and  by  the  plan  and  eleva- 
tion in  Plate  XLI  I.  the  breadths  and  diftances  of  the  Leaves, 
&c.  are  fully  exemplified  in  the  like  manner. 

In  the  Drawing  of  this  Capital,  the  young  Student  mull 
firft  accuftom  himfelf  to  exprefs  only  the  Leaves  in  grofs,  as 
exprelfed  in  this  and  the  XLIVth  Plate,  until  he  has  made 
himfelf  a  Matter  of  forming  their  out-lines  :  when  it  will  be 
a  pleafure  to  raffle  them,  as  exprefled  in  Plate  XLI  1 1,  and 
XLV. 

And  as  the  Capital  of  a  Pilader  has  all  its  Leaves  in  eaclt 
Face  in  a  direcl:  view,  contrary  to  thofe  of  a  Capital  to  a  Col- 
umn, and  is  one  fixth  of  a  Diameter  more  in  breadth  ;  I  have 
therefore,  to  explain  the  difference  and  parts,  ftiewn  in  Plate 
D  2  XLIV. 


26 


THE  BUILDER/s  JEWEL. 


XL IV.  the  Plan  and  Elevation  of  a  Capital  to  a  Pilafter,  m 
the  fame  manner  as  that  of  a  Column  in  Plate  XLII.  as  in- 
deed I  have  alfo  the  elevation  of  a  half  Capital  at  large,  with 
its  leaves  raffled,  as  thofe  of  Plate  XLIII. 

The  Compofite  Capital  explained.    Plate  LVIII. 

This  Order  is  called  Compoftte^  becaufe  its  Capital  is  compos- 
ed of  the  Ionick  and  Corinthian  Capitals  ;  that  is,  its  Abacus,  Vo- 
lutes, Ovolo  and  Aftragal  between  them,  are  the  very  Members 
which  form  the  modern  Ionick  Capital.  Its  two  Heights  of 
Leaves  are  the  very  fame  as  thofe  in  the  Corinthian  Capital  ; 
and  its  ftalks,  which  in  the  Corinthian  Capital  fmilh  with 
Volutes  and  Helices,  are  here  ftopt  by  the  Ionick  Volutes,  and 
made  to  finiih  inwardly  with  Hulks  on  Tendrels,  called  Cau- 
licoles. 

The  Height  of  this  Capital  is  the  fame  as  that  of  the  Co* 
rinthian^  and  is  divided  in  7  Parts  alfo,  of  which  the  upper  1 
is  the  Height  of  the  Abacus  ;  and  which  being  divided  in  2, 
and  the  upper  one  in  5  ;  the  upper  4  is  the  Height  of  the  Ovo- 
lo, and  the  lower  2  of  the  Fillet.  Divide  the  lower  half  of  the 
Height  of  the  Abacus  with  the  next  2  Parts  into  8,  and  then 
fmitfi  the  Volute  exactly  the  fame,  as  in  the  modern  Ionick 
Capital.    Plate  XXIV. 

Now,  as  the  remaining  part  of  this  Capital  is  entirely  Coritt* 
ihiany  as  before  proved,  it  is  needlefs  to  fay  more  thereof  ; 
but  that  it  may  be  fully  exemplified,  I  have  therefore 
fhewn  its  elevation  at  large  in  Plates  LIX.  and  LX.  as  well 
for  a  Pilafter,  as  for  a  Column  j  as  I  have  done  before  in  the 
Corinthian  Order. 

CHAP. 


THE  BUILDER'S  JEWEL 


27 


CHAP.  IV.    Of  Entablatures; 

A  m  Entablature  is  the  uppermoft:  or  lad  principal  Part  of  an 
Order,  (which  Vitruvius  called  Ornammt)  and  confifts  of  3 
Parts,  viz*  an  Architrave  a  Freeze  or  Prize,  and  a  Cornice. 

The  Heights  of  Entablatures  being  declared  in  Chap.  L  we 
are  now  to  obferve  that  their  projections  are  equal  to  their 
Heights,  in  all  the  orders,  excepting  the  Dorick,  and  that  only 
when  its  Mutules  are  introduced  ;  when  it  coniifts  of  half  the 
Entablature's  whole  Height. 

The  Heights  of  the  feveral  Entablatures  are  thus  divided 
into  their  Architraves,  Frizes,  Cornices,  &c* 

RULE  L  To  divide  the  Tufcan  Entalhture  into  its  Archl* 
trave,  Frize,  Cornice,  6c c.    Plate  III. 

Fir/},  Divide  the  given  height  Into  7  parts  ;  give  2  to  the 
Architrave,  2  to  the  Frize,  and  3  to  the  Cornice. 

Secondly,  Divide  the  height  of  the  Architrave  in  7  parts  ; 
give  2  to  the  lower  Fafcia,  4  to  the  upper  Fafcia,  and  1  to  the 
Tenia,  whofe  projection  is  equal  to  its  Height  ;  and  which 
being  divided  in  three,  give  1  to  the  projection  of  the  upper 
Fafcia. 

Thirdly,  Divide  the  Height  of  the  Cornice  in  3  ;  divide  the 
upper  1  in  4  ;  and  give  the  upper  1  part  to  the  Regula, 
aaid  the  other  three  to  the  Cima-recla.  Divide  the  middle  1 
in  6  ;  give  the  upper  1  to  the  Fillet,  and  the  other  5  to  the 

Corong, 


-28  t  THE  BUILDER5S  JEWEL* 


Corona.  Divide  the  lower  i  in  2  ;  give  the  upper  1  to  the 
Ovolo  ;  and  the  lower  half  divided  in  4,  give  the  upper  1  to 
the  Fillet,  and  the  other  3  to  the  Cavetto. 

By  the  Scale  of  Projection  is  feen,  that  the  Projection  of  the 
Corona  is  two  thirds  ;  the  Ovolo,  one  third  ;  and  the  Fillet  of 
the  Cavetto,  one  fixth  of  the  whole. 

Note,  By  well  underftanding  the  manner  of  proportioning 
this  Entablature,  (which  is  very  eafy)  the  others  following 
will  become  as  eafy  :  But  that  the  young  ftudent  may  not  be 
at  any  ftand  therein,  I  will,  for  a  further  explanation,  explain 
the  Entablatures  of  the  Dorick  and  Ionick  Orders,  in  the  fame 
manner. 

RULE  II.  To  divide  the  Dorick  Entablature  into  its  Archi- 
trave >  Frize,  Cornice,  &c.  Plate  XII. 

Fir/},  Divide  the  Height  in  8  parts  ;  give  2  to  the  Archi- 
trave ;  3  to  the  Frize,  and  3  to  the  Cornice. 

Secondly,  Divide  the  upper  1  of  the  Architrave  into  3,  and 
give  the  upper  1  to  the  Tenia  :  Divide  the  lower  2  in  6  ;  give 
the  upper  1  to  the  Fillet  over  the  Gutta's,  and  the  next  3. 
to  the  Gutta's. 

divide  the  lower  third  part  of  the  height  of  the  Cornice  in  3  ; 
and  give  the  lower  1  to  the  Cap  of  the  Triglyph.  Divide 
the  remaining  part  of  the  Cornice's  Height  in  4  parts,  and 
the  upper  1  part  in  4  ;  of  which  give  the  upper  1  to  the 
Regula,  or  upper  Fillet  on  the  Civia-recla  ;  and  the  lower  3  to 
the  Cma-retta*    The  next  part  divided  in  3,  half  the  upper 


THE  BUILDER'S  JEWEL. 


29 


i  is  the  Fillet  ;  and  the  remainder  the  Corona.  The  next 
part  being  alfo  divided  in  3,  the  upper  1  is  the  Capping  of  the 
Mutule,  and  the  lower  2  the  Mutule.  Laftly,  the  lower  4th 
part  divided  in  3,  half  the  upper  1  is  the  depth  of  the  ground 
to  the  Mutules  ;  and  half  the  lower  1  is  the  Fillet  to  the  Ovolo 
of  the  Bed-mould. 

The  projection  of  this  Cornice  (as  before  obferved)  is  half 
the  Height  of  the  whole  Entablature  ;  which  being  divided  in 
4,  as  on  the  Ciwa-refta,  has  the  projections  of  its  Members  de- 
termined, as  by  infpection  is  fhewn. 

Now  it  is  to  be  noted,  that  the  Breadth  of  a  Triglyph  is  al- 
ways equal  to  half  the  Column's  diameter  at  its  Bale  ;  that  its 
Channellings  and  Gutta's  are  found  by  dividing  the  breadth 
of  the  Triglyph  into  12  parts,  as  exhibited  at  large  in 
Plate  XIII.  That  the  Diftances  between  the  Triglyphs 
mull;  always  be  equal  to  the  Height  of  the  Frize,  and  there- 
fore will  become  exactly  fquare.  That  thefe  Intervals  or 
fquares  are  called  Metopes  ;  and  are  fometimes  enriched  with 
Rofes,  as  heie  exprefled,  or  otherwife  at  the  pleaiure  of  the 
Architect  ;  and  that  the  manner  of  forming  the  Planceer  of 
this  Cornice  is  fhewn  in  Plate  XIV. 

RULE  III.  To  divide  the  Ionick  Entablature  fate  the 
Jrditrave,  Frize,  Cormcey  &c. 

As  this  Order  has  two  Varieties  of  Entablatures,  viz*  the  one 
with  Dentules,  and  the  other  with  Modillions  :  I  have  there- 
fore fhewn  them  both;  and  by  explaining  of  cne,  the  other  will 
be  undcrftood, 

7i 


3° 


THE  BUILDER'S  JEWEL, 


To  divide  the  Ionick  Entallature  with  Dentules.  Plate  XXVIII. 

Firfiy  Divide  the  Height  in  10  Parts,  give  3  to  the  Archi- 
trave, 3  to  the  Frize,  and  4  to  the  Cornice. 

Secondly,  Divide  the  upper  1  Part  of  the  Architrave  in  4  ; 
give  the  upper  1  to  the  Fillet ;  the  next  2,  and  1  fourth  of 
the  lower  1  to  the  Cima-reverfa  ;  and  the  remaining  3  fourths 
of  the  lower  1  to  the  Bead.  Thefe  Members  together  are 
called  the  Tenia  of  the  Architrave,  whofe  Fillet's  Projection 
is  equal  to  their  whole  Heights. 

Thirdly,  As  the  Frize  of  this  Order  is  made  fwelling,  there- 
fore divide  the  Height  in  4,  and  on  the  middle  2  make  the 
Section  x9  on  which  defcribe  the  Curve  of  the  Frize. 

Fourthly,  The  Height  cf  the  Cornice  being  in  4  parts, 
divide  the  upper  1  in  4  ;  give  the  upper  1  to  the  Regula  or 
Fillet  on  the  Cima-recla,  and  the  remaining  2,  with  2  thirds  of 
the  lower  1 ,  to  the  Cima-recla  ;  and  the  1  third  give  to  the 
Fillet  on  the  Cima-reverfa. 

Divide  the  next  part  in  4  ;  give  the  upper  1  to  the  Cima- 
recla,  and  the  other  3  to  the  Corona. 

Divide  the  next  or  3d  part  in  6  ;  give  the  upper  3  to  the 
Ovolo,  the  next  1  to  its  Fillet,  and  the  next  1  to  the  Fillet  be- 
tween the  Dentules. 

Divide  the  lower  1  in  3,  the  upper  1  will  terminate  the 
depth  of  the  Dentules.  Divide  the  middle  1  in  3,  and  the 
upper  1  will  be  the  Depth  cf  the  Denticule  or  Fafcia,  on 

which 


THE  BUILDERS  JEWEL. 


which  the  Dentules  are  fixed,  and  the  remains  will  be  the 
Cima-reverfz,  and  lower  Member  of  the  Entablature. 

The  Projection  is  divided  into  4  principal  Parts,  as  by  the 
Scale  againft  the  Frize  is  (hewn  :  by  which  its  Members  are 
terminated,  as  by  infpeclion  is  plain. 

To  divide  the  Ionic k  Dentules. 

In  an  Entablature  over  a  Column,  divide  the  Di fiance  be- 
tween die  Central  Line,  and  the  Upright  of  the  Shaft  at  its 
Neck,  into  10  Parts  ;  give  2  Parts  to  the  Breadth  of  a  Dcntule, 
and  1  to  an  Interval.  Eut  in  an  Entablature  over  an  undi- 
minifhed  Pilafler,  divide  the  aforefaid  Diftance  into  1 2  Parts, 
and  proceed  as  before. 

Note 9  The  Breadth  of  a  Dentule  is  5  Minutes,  and  of  an 
Interval  2  Minutes  and  a  half ;  which  are  defcribed  at  large 
in  Plate  XXX. 

Now,  as  the  Icnick  Entablature  with  Modilions,  as  ex- 
prefled  in  Plate  XXIX.  has  its  Members  proportioned  in  lik^ 
manner,  I  therefore  need  only  to  note,  That  die  Breacih  of 
each  Modilion  is  10  Minutes  ;  that  the  Diilance  or  Interval 
between  them,  is  25  Minutes  in  an  Entablature  to  a  Column  ; 
and  30  Minutes  in  an  Entablature  to  an  undiminiihed  Pilailer. 
And  that  the  Curve  of  die  Sophete  of  the  Ionick  Modilion  is 
defcribed  at  large  in  Plate  XXX.  as  following. 

Tie  Height  and  Projefiure  being  before  found, 

Divide  the  Length  in  6  Parts  ;   and  on  the  Point  5  ere& 
the  Perpendicular  5  a  equal  to  2  Parts  and  a  hsdf ;  alfo  from 
E  the 


THE  BUILDER^  JEWEL. 


the  Point  2,  let  fall  the  Perpendicular  2  b  equal  to  1  Part  and 
a  half,  and  draw  the  Line  a  b.  On  the  Point  2,  defcribe  the 
Arch  1  d  ;  on  the  Point  b,  the  Arch  d  c  ;  and  on  the  Point  a> 
the  Arch  c  5. 

Note,  The  manner  of  forming  the  Return  of  the  Planceer  of 
this  Cornice  is  Ihewn  in  Plate  XXXI. 

RULE  III.  To  divide  the  Corinthian  Entablature  into  its 
Architrave,  Prize,  and  Cornice.    Plate  XLVI. 

1 .  Divide  the  Height  into  1  o  Parts  ;  give  3  to  the  Archi- 
trave, 3  to  the  Frize,  and  4  to  the  Cornice. 

2.  Divide  the  Height  of  the  Architrave,  and  of  the  Cornice, 
each  in  5  Parts,  and  fab-divide  them  as  exhibited  ;  and  then 
proceed  in  every  refpecl  as  in  the  preceding  Orders. 

Note,  That  though  the  Dentules  are  exprelTed  in  this  Cor- 
nice, yet  they  are  not  always  ufed. 

That  the  Breadth  of  the  Modilions  Is  10  Minutes,  as  before  m 
the  lonkk,  but  their  Diftances  are  greater. 

The  Interval  between  Modilions  in  a  Cornice  over  Columns 
is  25  Minutes;  and  in  a  Cornic^over  undiminiihed  Pilaftcrs 
30  Minutes. 

To  render  the  Parts  of  this  Modilion  plain  and  intelligible, 
I  have  ihewn  it  at  large  in  Front  and  Profile,  with  its  Meafures, 
in  Plate  XLVII.  wherein  Fig.  A  reprefents  the  Eye  of  its 
Volute  at  large,  with  the  Centers  numbered  ;  on  which 

its 


the  builder's  jewel.  33 

its  Curves  are  defcribed  in  the  very  fams  manner,  as  the  Vo- 
lute of  the  hnkk  Capital. 

Between  the  Modilions  the  Planceer  of  the  Sophete  of  the 
Corona  is  enriched  with  Roies  m  hollow  Pannels,  called  Cof- 
fers, as  expreffed  in  Plate  XLVIII.  which  alfo  fliews  the  man- 
ner of  returning  the  Sophete  at  an  external  Angle. 

RULE  IV.  To  divide  the  Compofite  Entablature  into  its 
Architrave,  Prize,  and  Cornice.  Plate  LXI. 

Fir/},  Divide  the  Height  into  ic  Parts  ;  give  3  to  the  Arch- 
itrave, 3  to  the  Frize,  and  4  to  the  Cornice. 

Secondly,  Divide  the  Heights  of  the  Architrave  and  of  the 
Cornice,  each  into  4  ;  fubdivide  their  Parts,  draw  in  and  ter- 
minate their  Members  by  the  Scale  of  Projection,  as  before 
done  in  the  preceding  Orders.  The  manner  of  enriching 
the  Planceer  of  the  Corona  of  this  Cornice,  and  returning  it  at 
an  external  Angle,  is  exhibited  in  Plate  LXIT. 

CHAP.  IV.   Of  Doers,  Window,  Porticos,  Arcades,   and  the 
Inter  colummation  of  Columns  in  general. 

That  the  young  Student  may  have  Plcafure  in  the  Pro- 
cefs  of  his  Study,  I  have  given  him  an  Example  of  a  Door 
fquare  and  circular  headed,  with  circular  and  pitched  Ped- 
iments, a  Window,  a  Portico,  and  an  Arcade,  with  their 
Imports  and  Architraves,  in  each  of  the  firft  4  Orders  ;  which 
immediately  follow  their  refpectivc  Entablatures  ;  and  which 
having  their  principal  Parts  determined  by  their  Meafjus 
E  2  affixed, 


34 


THE  BUILDER'S  JEWEL. 


affixed,  need  no  other  Explanation.  And  in  order  to  fur- 
iher  enable  him  in  the  Art  of  Defigning,  I  have  fhewn  the 
proper  Intercolumniations,  or  juft  Diftances,  that  the  Columns 
of  every  Order  muft  be  placed  from  each  other,  when  em- 
ployed in  Colonnades,  &c.  by  which  he  may  form  new 
Defigns  at  his  Pleafure.  See  Plates  VI.  XVII.  XXXIV. 
XXXV.  and  LIII. 

CHAP.  V.  Of  Pediments,  and  the  Manner  of  finding  their 
Peaking  and  returned  Mouldings  for  their  Cornices,  and  for 
Capping  of  their  raking  Mutules  and  Modi  lions. 

Pediments,  which  the  French  call  Frontons,  from  the  Latin 
Frons,  the  Forehead,  are  commonly  placed  over  Windows, 
Doors,  Porticos,  £sfr .  to  carry  off  the  Rains,  and  to  enrich  the 
Order  on  which  they  are  placed. 

Pediments  are  either  entire,  or  open  5  and  thofe  are  ftraight, 
circular,  compound;  &c. 

An  entire  ftraight  Pediment  is  generally  called  a  pitched 
Pediment  5  as  the  lower  Pediment  in  Plate  LXIX.  And  an 
entire  circular  Pediment  is  generally  called  a  Compafs  Pedi- 
ment, as  the  upper  Pediment  in  Plate  LXIX. 

When  a  Pediment  confifts  of  more  than  one  Arch,  as  thofe 
in  Plate  LXXI.  and  LXXII.  they  are  called  entire  compound 
Pediments. 

Open  Pediments  are   thofe,  whofe  raking  Members  are 
ftopt  in  feme  certain  Place  between  the  Points  of  their 
Sprififc  and  their  Faftigium  or  vertical  Point  ;  as  thofe  in 
*     D  Plate 


THE  BUILDER*S  JEWEL. 


35 


Plate  LXIIL  die  lower  Pediment  in  Plate  LXXI.  and  the  up. 
per  in  Plate  LXXIV. 

Entire  Pediments  are  the  firft  kind  that  were  made,  and 
were  originally  placed  to  Porticos  at  the  Entrances  into  Tern- 
pies  ;  but  now  we  place  them  to  Frontifpieces  of  Doors, 
Windows,  fijfa  for  Ornament  and  Ufe. 

As  the  entire  Pediment  by  its  reclining  Surfaces  carries 
off  and  difcharges  the  Rains  at  its  Extremes,  therefore  none  but 
entire  Pediments  ihould  be  employed  abroad  ;  whilft  the 
broken  or  open  are  employed  for  Ornament  only  withiniide, 
where  no  Rains  can  come. 

'Tis  true,  we  may  daily  fee  open  Pediments  placed  without- 
fide,  as  is  done  by  Inigo  Jones  at  Shaft/bury  Houfe  in  slderf 
gate-Jireet,  London.  But,  furely,  nothing  can  be  fo  abfurd, 
(unlefs  'tis  the  placing  of  an  entire  Pediment  withinfide  a 
Building,  where  no  rains  can  fall  ;  as  done  by  Mr.  Gikbs* 
within  the  church  of  St.  Mary  le  Strand)  bef  aufe,  by  their 
being  open,  they  receive  the  Rains,  and  difcharge  them  in 
Front,  as  a  ftraight  and  level  Cornice  doth  ;  and  therefore  ot 
no  more  ufe. 

As  Pediments,  when  well  applied,  are  very  great  Enrich- 
ments to  Buildings,  and  in  many  cafes  are  very  ufeful,  I  have 
therefore  given  14  Varieties  for  the  young  Student's  Practice, 
with  their  Meafures  affixed  ;  by  which  they  may  be  drawn 
and  worked  of  any  Magnitude  required.  Vide  Plates 
LXIX.  <Jc. 

1&  the  working  ©f  Pediments,  the  chief  Difficulty  is,  to 

form 


36 


THE  BUILDER'S  JEWEL* 


form  the  Curves  of  the  Raking  and  Returned  Cornices,  that 
fiiall  exactly  accadeer,  or  meet  at  their  Mitres  :  which  may  be 
truly  worked,  as  following, 

RULE.  To  defcribe  the  Carve  of  the  Raking  Cima-recla 
of  a  Pediment,  having  the  Curve  of  the  ftraight  or  level  Cornice 
given.    Plate  LXV. 

Let  a  b  g  be  the  given  Cima-recla  ;  divide  its  Curve  in  4 
equal  Parts  at  the  Points  d  ef,  and  draw  the  Ordinates  i  f  k  e, 
and  alfo  g  d  ;  from  the  Points  d  e  f  draw  the  raking  Lines 
fq,  e  r,  dx  ;  and  the  perpendicular  Lines  d  h,  e  /,  fm.  In 
any  Place,  as  at  ?i  0,  draw  a  right  Line  at  right  Angles  to  the 
Raking  Lines  ;  and  making  the  Ordinates  in  Fig.  B,  as  nv  q> 
n  r,  t  sy  equal  to  the  Ordinates  if  k  e,  g  d,  to  Fig.  A,  through 
the  Points  q  r  /,  trace  the  Curve  p  q  r  s  n  ;  which  is  the  Curve 
of  the  Raking  Gi?na-recla  required.  And  tho',  ftrictly  fpeak- 
ing,  each  half  is  a  Part  of  an  Ellipfis  ;  yet  if  Centers  be  found 
that  fhall  defcribe  the  Arch  of  a  Circle  to  pafs  through  the 
three  Points,  p  q  r,  and  r  s  n9  it  will  not  be  in  the  power  of  the 
moil  mquifittve  Eye  to  difcover  the  Difference. 

To  defcribe  the  Curve  of  the  returned  Cornice. 

From  p  Fig.  C,  fet  back  p  0  the  Projection  b  g  in  Fig.  A, 
and  draw  the  perpendicular  0  n,  on  top  of  the  Fillet  p  0  ;  make 
the  DiPcances  p  t,  t  v,  v  <tv,  equal  to  the  Diftances  b  k>  k  I,  I  m 
in  Fig.  A  ;  and  drawing  the  Lines  <w  x,  v  r,  t  g>  parallel  to 
the  perpendicular  0  n>  they  will  cut  the  Raking  Lines  in  the 
Points  qr  s  x.    From  the  Pokit /,  through  the  faid Points  to  », 

trace 


THE  BUILDER'S  JEWEL. 


37 


trace  die  Curve  p  q  r  s  v,  which  is  the  Curve  of  the  Returned 
Cima-rccla,  as  required  ;  for  its  Ordinates  at  thofe  Points  are 
equal  to  the  Ordinates  in  Figure  A. 

By  the  fame  Rule,  the  Curves  of  the  Raking  and  Returned 
Ovolo's,  Plate  LXVL  the  Raking  and  Returned  Cavetto's, 
Plate  LXVII.  and  the  Raking  and  Returned  Cin/a-reverfa ; 
for  the  Capping  of  Raking  Mutules  and  Modilions,  Plate 
LXVIII.  are  found,  as  is  evident  to  the  firft  View. 

CKAP.  VI.    Of  Block  and  Container  Cornices •,  Ruftkk  £hioins, 

Cornices  and  Coves,  proportioned  to  Rooms  of  any  Height, 

sfngle-B  rackets,  Mouldings  for  Tabernacle  Frames,  Pounds 
and  Centering  for  Groins. 

I.  Of  Block  Cornices  I  have  given  3  Varieties  in  Plate 
LXXV.  where  I  have  firft  fhewn  them  in  fmall,  to  esprefs  the 
Breadtli  of  their  Block-TruDes,  and  Diflances  at  which  they 
are  to  ftand  ;  as  likewife  the  manner  of  applying  them  over 
Ruftic  Quoins  ;  and  fecondly  at  large,  the  better  to  exprefs  the 
Divifion  of  their  Members. 

II.  In  Plate  LXXIX.  I  have  given  an  Example  of  a  Can- 
taliver  Cornice  at  large,  which  in  lofty  Rooms  under  a  Cove 
has  a  very  grand  and  noble  efFect.  The  Breadtli  of  a  Can- 
taliver,  is  one  4th  of  its  Height,  which  is  equal  to  the  Height 
of  the  Prize,  and  the  Dillance  they  are  placed  at  is  the  fame 
as  their  Height  ;  thereby  making  their  Metcps  exactly  a  geo- 
metrical Square,  as  in  the  Dor  'uk  Order. 

III.  Covus 


3« 


THE  BUILDER'S  *JE\VEL. 


III.  Coves  to  Ceilings  are  of  various  Heights  ;  as  one  third, 
one  fourth,  one  fifth,  one  fixth,  two  fevenths,  two  ninths,  EsV. 
of  the  whole  Height. 

A  Cove  of  one  third,  as  Fig.  A.  Plate  LXXXI,  is  beft  for 
a  lofty  Room  ;  and  when  Windows  are  made  therein,  the 
Groins  make  a  very  agreeable  Figure,  and  take  off  the  feem- 
ing  Heavinefs,  which  an  entire  Cove  of  a  large  Height  impofes 
©n  the  Eye. 

The  Curve  of  this  Cove  x  h  is  a  Quadrant  of  a  Circle  des- 
cribed on  the  Center  e  ;  as  alfo  is  the  Curve  a  c  of  the  fame 
Radius,  defcribed  on  the  Center  b.  To  find  the  Center  b, 
after  having  fet  out  the  Diftances  of  the  Columns  at  9  Diame- 
ters and  a  half,  and  defcribed  the  Cove  x  b>  as  afcrefaid  ;  make 
d  b  equal  to  a  d. 

A  Cove  of  one  fourth,  as  Fig.  A.  Plate  LXXTX.  is  alfo  fit 
for  a  lofty  Room,  as  a  Hall,  Saloon,  &c.  which  is  thus  pro- 
portioned :  Divide  the  Height  in  20  Parts  ;  give  5  to  the 
Cove,  and  2  to  the  Entablature. 

To  defcribe  an  Angle-Bracket  for  any  Cove,  fuppofe  for 
Fig.  B. 

.Let  a  h  c  be  a  Front  Bracket,  and  a  f  the  Bafe  over  which 
the  Angle  Bracket  is  to  Hand.  In  C  draw  Ordinate*  from 
its  Carve  to  its  Bafe  a  n9  at  any  Diftances,  and  continue  them 
till  they  meet  a  /  the  Bafe  of  the  Angle-Bracket,  from  whence 
raife  Ordinates  at  right  Angles  to  the  faid  Bafe,  and  making 
than!  refpectiv-yiy  equal  to  thofe  in  Figure  C  5  through  their 

Extremes 


THE  BUILDER^  JEWEL.  39 

Extremes  trace  the  Curve  a  n  e,  which  is  one  Quarter  of  an 
Ellipfis,  and  the  Curve  of  the  Angle-Bracket  required. 

A  Cove  of  one  5th,  as  Fig.  L  Plate  LXXIX.  is  fit  for  a 
Room  of  State,  and  thus  proportioned,  viz.  Divide  the 
Height  in  5  ;  give  one  to  the  Cove,  and  one  third  of  the  next 
to  the  Cornice,  which  is  Dorick  without  Mutules,  and  repre- 
fented  at  large  by  Fig.  H. 

A  Cove  of  one  6th,  as  the  two  Coves  in  Plate  LXXX.  is 
fit  for  Dining  Rooms,  &c.  and  is  thus  proportioned.  Divide 
the  Height  in  30  Parts  ;  give  5  to  the  Cove,  and  1  to  the 
Cornice. 

A  Cove  of  two  7ths,  as  Fig.  B,  Plate  LXXXI.  is  fit  for  a 
Study  or  Bed-Chamber,  and  even  for  a  Hall ;  as  herein  ex- 
prelTed,  and  is  thus  proportioned  :  Divide  the  Height  in  7  ; 
give  2  to  the  Cove,  and  1  to  the  Entablature,  which  is  Dorick. 

IV.  In  Plate  LXXVI.  I  have  fhewn  how  to  propor- 
tion the  Tufcany  Dorick,  lonick,  EsV.  Cornices  to  the  Height 
of  any  Room  :  a  Work  known,  or  at  leail  pra&ifcd,  but 
by  few. 

I.  To  proportion  the  Tufcan  Cornice  to  a  Room  of  any  Height* 

Divide  the  Height,  from  the  Floor  or  Dado,  in  5,  and  the 
upper  1  in  5  ;  of  which  give  3  to  the  Height  of  the  Cornice, 
and  2  to  the  Breadth  of  its  Stile  and  Height  of  its  Rail, 
Fig.  A. 

II.  To  proportion  the  Dorick  Cornice  to  a  Room  of  any- Height 

Fig.  B. 

Divide  the  Height  in  4,  and  the  upper  1  in  10  j  of  which 
F  give 


4o  THE  builder's  jewel* 


give  3  to  the  Height  of  the  Cornice,  and  2  to  the  Breadth  of 
its  Stile  and  Height  of  its  Rail. 

III.    To  proportion  the  Ionick,   Corinthian,   or  Compofite 
Cornices  to  the  Height  of  any  Roo7?i9  Pig.  C. 

Divide  the  Height  in  3,  and  the  upper  one  in  5  ;  of  which 
give  the  upper  1  to-  the  Height  of  the  Cornice,  and  3-5ths  of 
the  next  1  to  the  Height  of  the  Rail,  and  to  the  Breadth  of 
the  Stile. 

V.  In  Plate  LXXVII.  I  have  given  eight  different  Mould- 
ings for  Pannels  ;  and  in  Plate  LXXVIII.  four  different 
Mouldings  for  Tabernacle  Frames,  with  proper  Enrichments, 
and  their  Meafures  affixed  ;  by  which  they  may  be  drawn  and 
worked,  of  any  Magnitude  required. 

VI.  In  Plate  LXXXII.  I  have  fhewn  the  manner  of  find- 
ing the  Curves,  of  the  neceiTary  Ribs  for  Groins,  by  one 
general  Rule,  as  follows. 

In  Fig.  A,  let  a  b  c  d  be  the  Plan,  and  the  Semi-eircle  a  c  h 
$n  End  Rib,  and  ef'its  Height.  Draw  the  Diagonal  a  d,  as 
alfo  th§  Ordinates  1234,  on  the  Semi-circle  Rib,  which 
continue  till  they  meet  the  Diagonal,  in  the  Points  5678; 
from  whence  raife  right  Lines  perpendicular  to  a  d,  respec- 
tively equal  to  the  ordinates  1  234;  and  then  tracing  the 
Curve  through  their  Extremes,  it  will  be  the  Curve  for  the 
Diagonal  Rib,  as  required. 

By  the  fame  Rule,  the  Ribs  for  all  other  kinds  of  regular 

•r 


THE  BUILDER'S  JEWEL. 


41 


or  irregular  Groins,  are  found,  be  their  Plans  what  they  will, 
and  their  Arches  femi-circular,  femi-elb'ptica],  or  Scheme  ;  as 
is  evident,  by  Figures  13  C  D  E  and  F  ;  which  a  little  Infpec- 
tion  will  make  evident  to  the  meaneft  Capacity. 

CHAP.  VII. 

Of  Trnfs'd  Partitions,  Trufs'd  Girders,  Naked  Flowing,  See. 

I.  In  Plate  LXXXIIL  are  three  Varieties  of  Trnfs'd  Parti- 
tions,  of  40,  50,  and  60  Feet  bearing,  for  Granaries,  Ware- 
houfes,  wherein  great  Weights  are  laid ;  of  which  the 
middle  one  is  for  two  Stories  Height. 

II.  In  Plate  LXXXIV.  the  Figures  ABC  reprefent  three 
Varieties  of  Trufs'd  Girders  ;  which  ought  not  to  exceed 
25  or  30  Feet  in  Length  ;  and  Figure  D  is  a  Girder  cut 
Camber,  which,  for  Lengths  from  15  to  20  Feet,  will  do 
without  being  Trnfs'd,  as  the  preceding. 


Tht  Scantlings  of  Girders  Jhculd  be? 


Lengths 
from 


Feet 
"  12  ~ 

y 
18 
2 1 

24 


1*/  J 


to 


Feet 

18 
2 1 

30  J 


Inches 
'  10" 

1 1 

12 

*3 

14 

L15J 


to  be  <      >  by 


Inches. 
8 

9 
10 
1 1 
12 
x3 


Note,  That  Girders  fhould  have  at  leaft  9  Inches  bearing  in 
the  Walls,   and  be  bedded  on  Lintels,  kid  in  Loam,  with 
F  2  Arches 


4* 


THE  BUILDER*S  JEWEL. 


Arches  turned  over  their  Ends,  that  they  may  be  renewed  at 
any  Time  without  Damage  to  the  Pier. 

HI.  In  the  upper  Part  of  this  Plate,  I  have  ftiewn  3  Bays 
of  Joift,  or  naked  Flooring  ;  wherein  the  two  outer  ones 
have  only  their  binding  Joifts,  exprefs'd  ;  and  that  in  the  mid- 
dle with  their  Bridging  Joifts,  (or  Furring  Joifts)  as  called  by 
fome.  In  this  kind  of  Flooring  'tis  to  be  noted,  that  bind- 
ing Joifts  are  fo  framed  as  that  their  under  Surface  be  level 
with  the  under  Surface  of  the  Girder,  and  the  upper  Sur- 
face of  their  Bridgings  with  the  upper  Surface  of  the 
Girder. 

The  Diftance  of  binding  Joifts  ftiould  not  exceed  3  Feet  and 
a  half,  or  4  Feet  in  the  clear  5  and  their  Scantlings  ftiould  be 
as  follow,  viz. 


Feet  Inches 


If  their 
Length  be 


Bridging  Joifts  ftiould  be  laid  at  1  Foot  in  the  clear,  and 
their  Scantlings  ftiould  be  3  by  4  ;  3  and  a  half  by  4,  or  4  by 
4,  Esfr. 

In  common  Flooring,  wrhere  neither  Binding  or  Bridging 
Joifts  are  ufed,  the  Scantlings  of  Joifts  ought  to  be  as  fol- 
lows, viz. 

Feet  Inches 

jgu  §}  ^sr  g|  *  HI 

•  Note, 


THE  BUILDER^  JEWEL. 


43 


Vote j  No  Joifts  to  exceed  1 2  Feet  in  Length  ;  to  have  at 
leaft  fix  Inches  Bearing,  and  that  on  a  Lintel  or  Bond-Timber  ; 
and  their  Diftance  in  the  clear  not  to  exceed  one  Foot.  'Tis 
alfo  to  be  obferved,  that  all  Joifts  on  the  Breafts  and  Backs 
of  Chimneys  be  framed  into  Trimming  Joifts  (whofe  Scant- 
lings are  to  be  the  fame  as  thofe  of  Binding  Joifts)  at  6  or 
8  Inches  Diftance  behind,  and  12,  16,  Iftc,  Inches  before, 
as  a  a. 

CHAP.    VIII.    Of  Roofs. 

The  Requifites  to  Roofing,  are  the  Scarfing  and  completing 
of  Raifings,  or  Wall- Plates,  £sV.  to  determine  the  neceffary 
Height  of  the  Pitch,  agreeable  to  the  Covering  ;  to  find 
the  Lengths  of  Principal  and  Hip-Rafters,  and  to  Back 
them  when  necefTary  ;  to  contrive  the  proper  TrufTes  for  to 
ftrengthen  the  Principal  Rafters  ;  and  to  lay  out  in  Ledge- 
ment  the  feveral  Skirts ;  thereby  to  determine  the  Quantity 
of  Materials  neceffary  ;  and  to  find  the  feveral  Angies  and 
Lengths  of  all  Parts  ;  fo  as  to  fet  out  Work,  and  fix  at  once, 
the  whole  in  a  Workman  like  manner,  and  in  the  leaft  time. 

Now  in  order  to  make  the  young  Student  a  Mafter  herein, 
I  have  fhewn. 

I.  In  Plate  LXXXV.  By  figures  CDEFGHIKLM  ten 
different  Manners  of  Scarfing  together  the  Raifmg  of  Roofs  ; 
which  is  the  firft  Work  to  be  done  ;  and  then  the  Beams  be- 
ing cogged  down  thereon  at  their  proper  Diftances,  which 
fliould  never  exceed  10  Feet  in  the  clear  ;  we  may  begin  to 
confider,  and  work  the  Superftrudure  to  be  raifed  thereon. 

The 


44  the  builder's  jewel. 

The  firft  thing  to  be  confidered  is  the  Height  of  the 
Pitch,  which  muft  be  determined  according  to  the  Covering  ; 
which,  if  with  plain  Tile  or  Slate,  the  true  Pitch,  as  Fig.  A, 
will  be  proper  :  But  if  with  Pan-tiles  or  Lead,  it  may  be 
much  lower.  But  here,  for  example's  fake,  we  will  fuppofe 
a  Roof  to  be  true  Pitch,  whofe  plan  is  rvtA9  Fig.  B,  and  whofs 
breadth  we  will  fuppofe  is  equal  to ^  4,  Fig.  A. 

To  find  the  Length  of  a  Principal  Rafter.  - 

Divide  g  4,  in  4  Parts  ;  on  g  and  4  with  the  Radius  of  3 
Parts,  make  the  Section  h  ;  then  draw  the  Lines  g  h>  and  /;  4  ; 
and  each  is  the  Length  of  a  principal  Rafter  required. 

To  find  the  Length  of  the  Hip  Rafters. 

Draw  the  Central  Line  0  a,  and  the  Diagonals  or  Bafes, 
over  which  the  Hip  Rafters  are  to  fland  ;  as  r  a,  t  a,  a  v,  and 
ah;  make  a  t,  a  h>  and  a  r,  in  Fig.  A.  equal  to  a  t,  a  h,  and 
a  r,  in  Fig.  B,  and  draw  the  Lines  h  t,  h  h9  and  h  r  ;  then 
h  r  is  the  Length  of  the  Hip  Rafter  rp  ;  h  h  is  the  Length  of 
the  Hip  g  h  ;  and  q  v>  and  h  t  is  the  Length  of  the  Hip  t  s. 

Or  otherwife,  on  the  End  of  the  Diagonal  r  a,  raife  the 
Perpendicular  a  q  equal  in  Height  to  h  a  in  Fig.  A,  and  draw 
the  line  r  />,  which  is  the  length  of  that  Hip,  and  equal  to  h  r 
in  Fig.  A,  as  before.  By  the  fame  Rule  you  may  find  the 
lengths  of  all  the  other  3  Hips. 

To  find  the  Angle  of  the  hack  of  any  Hip  Rafter. 

Through  any  Point  of  its  Bafe,  as  c  in  Fig.  B,  draw  a  right 
Line  at  right  Angles,  as  f  b,  cutting  the  Outlines  of  the  Plan 
in  f  and  &.    From  the  Point  <r,  hi  fall  a  Perpendicular,  as 


THE   BUILDER'S  JEWEL. 


45 


*  dy  on  the  Hip  g  h  ;  and  make  c  €  equal  to  c  J.  Draw  the 
Lines />,  and  b  r,  and  the  Angle  b  ef  is  the  Angle  of  the 
Back  required. 

To  lay  out  a  Roof  in  Ledgemcnt.    Plate  LXXXVI. 

Let  bide,  be  a  given  Plan  ;  a  h,  Fig.  B,  the  given  Pitch  ; 
and  b  gy  b  g  a  Pair  of  Principal  Rafters  agreeable  thereto. 

By  the  preceding,  draw  the  Ridge-Line  a  a,  and  the  Dia- 
gonals a  dy  a  cy  and  a  by  a  i.  In  Fig.  B,  make  a  c9  a  dy  and 
a  by  equal  to  the  Diagonals  a  dy  a  and  a  by  a  /,  in 
Fig.  A.  Through  the  Points  a  a  in  Fig.  A,  draw  the 
two  beams  q  k,  and  e  4.  Make  r  qy  ft ;  and  k  /,  4  ;;/, 
each  equal  to  the  Length  of  a  Principal  Rafter,  as  b  gy  Fig. 
B  ;  and  draw  the  Lines  d  s>  s  r,  r  by  and  /  /,  /  ttf,  m  c.  On 
the  Points  B  and  /,  in  Fig.  A,  with  the  Radius  h  b  (the 
Length  of  the  Hip)  make  the  Section  /,  and  draw  the  Lines 
b  t  and  /  /. 

On  the  Point  dy  in  Figure  B,  with  the  Length  h  d  in  Fig. 
B,  and  on  c  with  the  Length  h  c,  make  the  Section  0  ;  then 
drawing  the  Lines  d  0  and  c  0,  the  Skirts  of  the  whole  Roof 
is  laid  ;  which  fill  up  with  fmall  and  Jack  Rafters  at  Pleafure. 

Now  when  the  Skirts  of  a  Roof  are  thus  drawn  on  Paper, 
and  are  cut  out  round  at  their  extremes,  and  be  truly  bent  or 
turned  up  on  the  Outlines  of  the  Railing,  as  b  /,  b  dy  d  <r,  and 
c  iy  they  will  all  come  truly  together,  and  become  a  model  of 
the  Rcof  required,  wherein  every  Rafter  may  be  exprefTed  in 
its  Place,  and  the  juft  Lengths  &ad  Quantity  known  to  a  very 
greut  exacmcfi. 

By 


THE  BUILDER'S  JEWEL. 


By  the  fame  Rule,  the  irregular  Roof,  PL  LXXXVII,  is 
laid  out  in  Ledgement,  and  its  Requifites  found,  as  is  evident 
at  the  firft  View. 

Note>  As  this  plan  hath  not  parallel  Sides,  every  Pair  of 
Rafters  will  therefore  be  of  different  Lengths,  although  the 
Height  of  their  Pitch  is  the  fame,  and  fo  confequently  every 
Rafter  muft  be  backed  by  taking  away  a  Triangle,  as  a  e  b 
Fig.  D,  and  then  the  Sole  of  the  Foot  of  a  Rafter  will  be  as 
c  a  d  b. 

The  following.  Plates  confifling  wholly  of  TruiTes  for 
Roofs  and  Domes,  need  no  Explanation  more  than  their  own 
Figures  exprefs,  to  which  I  refer. 


The    Tuscan    Entablature.  TIHL. 


Tuscan  Doors 


1 


« 


PL  !4- 


TJie  P/anceer  of  Che  Z>orick 
Cornice,  c&an  external 
triple  ^J?ide  FtatcXII. 


r1    3  3 


7? 


DoRICK  WlN' DOW. 


i    The  Ioxlck  Capital its  Semi  Flax.         PI. 14. 


« 


P1.2S. 


The  fllanne r  of  dividuuj  the  Flute*  V T\ llet^  ofTitost 

Ft*?. 


J4 


/  l^  UUU  U  kJ.  k^j 


1/1  J  \/\  J  ir\  3  v'7\ 


3/  Parts. 


The  Ioxick  Dentltle  Entablature. 


Ft  *8. 


The  lonick  Modi  lion     Entablature  .     PI.  29. 


IOXICK  ViIXDOW. 


Tt.  S3. 


PI.  3  5. 


8 
3 


lb 

NO 


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The  Cormthistn  Base  arid  Capital,  le  a  Column. 


i 


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6 


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*  ■'  '  irfote.  TJif  </t stance 


4 


\^  hchveen  yCenteral  lin& 
of  MoJtftotfs  we  r    n  rA 


JT  Mottrtroi/s  ever  n  )trf 
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'  Mnoi-  their  0  nut  — - 
Breadth  in  /,(>tL  Cases 
jo  Minutes. 


m 


Tlif  CORINTHIAN'  Mo  BILLION,  ejcplaiiz'dsfltf- 


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The  Corrnthian  Irufs  explained.  Ft.  5i 


The  Corinthian  Entablature  .Jar  Doors  h^iruiorvs  *£c.  PI  51 


\% 


T 


~7 


PI. 5 3. 


I 


k 


i 


i 


■ 


1 


i 


The  Composite  Ent.\blature.  PL  6l. 


The Dorick ScJonick  ope-n  Pediment  E&plcurid*  PI. 6 


The  Rakvruy  Cav&tto 


■ 


1 


To  Proportion  (jTrmces  to  Rooms 


Uiscan. 


A 


3 


.ji. 


p/apy  Height.  P?  j(\ 


DoricA 


B 


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Ion  irk. 


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■ 


AC  ova  4£o£the  entire  Heigh  '&  Pi .  Jj? . 


2  -  ;  ■ 

Coi+es  oof  the  entire  Height .  PI.  So. 


Ti^uficl  Partitions.  Pl.Sa. 


60  Feet. 


Trussed         Gi  rote  /v. 


♦ 


I 


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* 


4 


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